Conventional detergents used in warewashing include alkaline detergents. Alkaline detergents, particularly those intended for institutional use, can affect the appearance of metals, particularly soft metals such as aluminum. For example, alkaline detergents can create blackening or corrosion on aluminum pans. Conventionally, alkaline detergents have contained phosphorous to reduce corrosion. However, increased regulation of the use of phosphorous in detergents has created a need to identify alternative anti-corrosion compositions.